Feasibility and efficacy of primary tractography during percutaneous catheter drainage

BACKGROUND

The indication of percutaneous catheter drainage (PCD) has expanded with the development of guiding modalities. Since serious complications still occur, efforts and new techniques have been continuously searched for safer PCD.

PURPOSE

To evaluate the feasibility and efficacy of primary tractography for establishing a safe needle pathway during PCD.

MATERIAL AND METHODS

A total of 42 patients (20 men, 22 women; mean age, 50.7 years) who underwent primary tractography during PCD were prospectively enrolled between April 2009 and August 2013. The locations of fluid collection included sub-phrenic (n = 8), between bowel loops (n = 21), pelvic cavity (n = 8), within solid organ (n = 2), and others (n = 3). The interposed anatomic structures were analyzed on the basis of primary tractography findings. Complications related to PCD or primary tractography were evaluated.

RESULTS

Interposition of any significant anatomic structure was confirmed in 10 of 42 patients (23.8%). The entrapped anatomic structures were the omental vessel (n = 4), bowel (n = 2), pleura (n = 2), bile duct (n = 2), and a branch of the left inferior epigastric artery (n = 1). In one patient, both the pleura and bile duct were interposed simultaneously. The technical and clinical success rates of PCD were 97.6% and 97.6%, respectively. No complications related to PCD or primary tractography occurred during the follow-up period.

CONCLUSION

Primary tractography is a simple and feasible method to evaluate the entrapment of normal anatomic structure during PCD. This method may aid in preventing possible serious PCD-related complications, such as bleeding and fistula.

Transthoracic needle aspiration: the past, present and future

Transthoracic needle aspiration (TTNA) has been used to diagnose disease in the lung for many decades. Thanks to advances in technology and cytopathology, the diagnostic power, accuracy, safety, and efficacy of TTNA are constantly improving. The transition from fluoroscopy to computed tomography (CT) has yielded better visualization, and ability to enhance sophistication of tools used to biopsy. In addition, needles are being refined for obtaining better biopsy samples and increased capabilities. Because of the minimally invasive nature of TTNA, it is becoming a strong alternative to surgical intervention. In the future, these developments will continue and TTNA will become more efficient, and potentially open a door to personalized medicine. However, there are complications due to this procedure, which include pneumothorax, hemorrhage, air embolism, and others which are very rare. Probability of complication increases when patients are older, have significant past medical history, have larger lesions, and are uncooperative during procedure. Indications, contraindications, and other considerations should be contemplated before a patient is elected for TTNA.

Percutaneous ablation of colorectal lung metastases

Lung metastasectomy can prolong survival in patients with metastatic colorectal carcinoma. Thermal ablation offers a potential solution with similar reported survival outcomes. It has minimal effect on pulmonary function, or quality of life, can be repeated, and may be considered more acceptable to patients because of the associated shorter hospital stay and recovery. This review describes the indications, technique, reported outcomes, complications and radiologic appearances after thermal ablation of colorectal lung metastases.

Improved outcome with combined US/CT guidance as compared to US guidance in percutaneous radiofrequency ablation of small renal masses

BACKGROUND

When performing percutaneous radiofrequency ablation (RFA) of small renal masses (SRM), use of optimized periprocedural image guidance is essential to secure curative outcome of the treatment.

PURPOSE

To retrospectively compare the short-term radiological and clinical outcomes of RFA under combined ultrasound (US) and computed tomography (CT) guidance with that of a previously performed US-guided series at the same institution.

MATERIAL AND METHODS

From November 2009 to November 2013, 60 patients (mean age, 70.1 years; range, 34-86 years) with renal masses measuring in the range of 13-50 mm in maximal diameter (mean diameter, 25.4 ± 6.8 mm) underwent percutaneous RFA with combined US/CT guidance. The technical success rate, recurrence-free survival, rate of complications, and the percentage change in the estimated glomerular filtration rate (eGFR) were compared with that of a previously published series of 41 patients with SRM treated with US-guided RFA between November 2002 and December 2008.

RESULTS

The tumor and patient characteristics were similar between the two treatment groups. The primary and secondary technical success rate was significantly higher in the group treated with combined US/CT guidance compared with the group treated with US guidance alone (100% and 100% vs. 82% and 91%, respectively). The local recurrence-free survival was significantly better in the combined US/CT-guided group than in the US-guided group (P = 0.016). There was no significant difference in the rate of overall complications (13% vs. 17%) or the mean percentage decrease in the eGFR after the respective treatment (1.1 ± 18.3% vs. 5.0 ± 11.7%).

CONCLUSION

The use of combined US/CT guidance when performing renal RFA resulted in superior primary and short-term outcome compared to the use of US guidance alone in patients treated at the same institution.

Palliation double stenting for malignant biliary and duodenal obstruction

The surgical management of patients with malignant biliary and duodenal obstruction is complex. Tumor excision is no longer possible in the majority of patients with malignant obstructive jaundice and duodenal obstruction. The aim of the present study was to evaluate the effectiveness of intraluminal dual stent placement in malignant biliary and duodenal obstruction. In total, 20 patients with malignant obstructive jaundice and duodenal obstruction, including 6 with pancreatic carcinoma, 11 with cholangiocarcinoma, 1 with duodenal carcinoma and 2 with abdominal lymph node metastasis, were treated with intraluminal stent placement. Bile duct obstruction with late occurrence of duodenal obstruction was observed in 16 cases, and duodenal obstruction followed by a late occurrence of bile duct obstruction was observed in 3 cases, while, in 1 case, bile duct obstruction and duodenal obstruction occurred simultaneously. After X-ray fluoroscopy revealed obstruction in the bile duct and duodenum, stents were placed into the respective lumens. Percutaneous transhepatic placement was employed for the biliary stent, while the duodenal stent was placed perioraly. The clinical outcomes, including complications associated with the procedures and patency of the stents, were evaluated. The biliary and duodenal stents were successfully implanted in 18 patients and the technical success rate was 90% (18/20). A total of 39 stents were implanted in 20 patients. In 2 cases, duodenal stent placement failed following biliary stent placement. Duodenal obstruction remitted in 15 patients, and 1 patient succumbed to aspiration pneumonia 5 days after the procedure. No severe complications were observed in any other patient. The survival time of the 18 patients was 5-21 months (median, 9.6 months), and 6 of those patients survived for >12 months. The present study suggests that X-ray fluoroscopy-guided intraluminal stent implantation is an effective procedure for the treatment of malignant biliary and duodenal obstruction.

Accuracy of MRI-Targeted in-Bore Prostate Biopsy According to the Gleason Score with Postprostatectomy Histopathologic Control--a Targeted Biopsy-Only Strategy with Limited Number of Cores

RATIONALE AND OBJECTIVES

Accuracy of ultrasound-guided biopsy and Gleason score is limited, and diagnosis of insignificant cancer with Gleason score ≤6 is frequent when extended biopsy schemes are used. We evaluated whether the magnetic resonance imaging (MRI)-targeted in-bore prostate biopsy correctly identifies the Gleason score of prostate cancer in histopathologic correlation after prostatectomy. Simultaneously a targeted concept is expected to keep down the rate of insignificant cancer.

MATERIALS AND METHODS

We compared retrospectively the Gleason score of the MRI-targeted in-bore biopsy with prostatectomy specimens in 50 men with prostate cancer. Endorectal MRI included T2-weighted imaging, diffusion-weighted imaging, dynamic contrast-enhanced imaging, and spectroscopy. Lesions with a prostate imaging-reporting and data system (PI-RADS) score ≥3 were considered. Upgrading and downgrading of tumors was evaluated, and significant upgrading was defined as a shift in Gleason score from 6 to 7 or more.

RESULTS

Gleason score was concordant in 66% of the patients, overall upgraded in 30% of patients, and downgraded in 4% of patients. Significant upgrading of the Gleason score from 6 to 7 occurred in eight patients; upgrading did not exceed one step in the Gleason score. After prostatectomy the Gleason score 6 was found in 20% of patients. The median number of cores obtained was 4 (range 2-6), and the median number of positive cores was 2 (range 1-4).

CONCLUSIONS

In-bore MRI-targeted biopsy offers good accuracy in the Gleason score with postprostatectomy histopathologic control when compared to the literature. A limited number of cores are sufficient to achieve these results. The fraction of insignificant cancer identified by targeted only-biopsy is low. Upgrading is restricted to one step in the Gleason score. Clinicians should be aware of positive findings in MRI and the biopsy technique used when assessing prostate biopsy results.

A novel and inexpensive ballistic gel phantom for ultrasound training

BACKGROUND

Ultrasonography use is increasing in emergency departments, and ultrasound education is now recommended in resident training. Ultrasound phantoms are used in many institutions for training purposes. The purpose of this study is to describe an inexpensive and simple method to create ultrasound-imaging models for the purpose of education and practice using clear ballistic gel.

METHODS

Clear ballistic gel is used to simulate tissue for firing practice and other military evaluations.

RESULTS

The transparent and durable ultrasound phantom we produced was clear and contained four vessel lumens. The images obtained using the phantom were of high quality and compared well to normal sonographic anatomy.

CONCLUSIONS

The clear ballistic brand gel is unique because it is inexpensive, does not dry out, does not decay, is odorless, and is reusable. The ultrasound images obtained using the phantom are realistic and useful for ultrasound education.

Interventional treatment of renal angiomyolipoma: immediate results and clinical and radiological follow-up of 4.5 years

BACKGROUND

Renal angiomyolipoma is rare, but many of these patients may have an acute debut with severe bleeding. These patients need urgent treatment with interventional embolization as an attractive option.

PURPOSE

To investigate the technical and clinical effect of this treatment and to evaluate long-term clinical outcomes with clinical control and radiological imaging.

MATERIAL AND METHODS

Eight patients with angiomyolipoma were treated with embolization. Five patients were treated acutely. Five patients were followed-up for mean 4.5 years with clinical and radiological examinations.

RESULTS

The renal angiomyolipoma decreased significantly from mean 7.2 cm to 2.9 cm after embolization (p = 0.04). Cortical infarctions of about one-third of the circumference of the embolized kidneys could be detected on follow-up examinations, but all patients had normal total kidney function. The bleeding was primarily stopped in all patients, however, in one patient bleeding from a lumbar artery was supplementary embolized within 24 h. In another case the interventional procedure ended up in embolization of the whole kidney as it was impossible to embolize all the feeding arteries selectively. One patient had a nephrectomy one month after embolization because of infection and re-bleeding and one patient after 2.5 years because of tumor size >4 cm. The technical success was 7/8 (88%) and clinical success was 6/8 patients (75%).

CONCLUSION

Selective embolization of renal angiomyolipoma is a minimally invasive and safe procedure with few complications. It is a nephron sparing alternative to renal resection. The reduction in tumor size after embolization is significant and long-lasting.

Magnetic resonance-guided regional gene delivery strategy using a tumor stroma-permeable nanocarrier for pancreatic cancer

BACKGROUND

Gene therapy is a very promising technology for treatment of pancreatic ductal adenocarcinoma (PDAC). However, its application has been limited by the abundant stromal response in the tumor microenvironment. The aim of this study was to prepare a dendrimer-based gene-free loading vector with high permeability in the tumor stroma and explore an imaging-guided local gene delivery strategy for PDAC to promote the efficiency of targeted gene delivery.

METHODS

The experimental protocol was approved by the animal ethics committee of Zhongshan Hospital, Fudan University. Third-generation dendrigraft poly-L-lysines was selected as the nanocarrier scaffold, which was modified by cell-penetrating peptides and gadolinium (Gd) chelates. DNA plasmids were loaded with these nanocarriers via electrostatic interaction. The cellular uptake and loaded gene expression were examined in MIA PaCa-2 cell lines in vitro. Permeability of the nanoparticles in the tumor stroma and transfected gene distribution in vivo were studied using a magnetic resonance imaging-guided delivery strategy in an orthotopic nude mouse model of PDAC.

RESULTS

The nanocarriers were synthesized with a dendrigraft poly-L-lysine to polyethylene glycol to DTPA ratio of 1:3.4:8.3 and a mean diameter of 110.9±7.7 nm. The luciferases were strictly expressed in the tumor, and the luminescence intensity in mice treated by Gd-DPT/plasmid luciferase (1.04×10(4)±9.75×10(2) p/s/cm(2)/sr) was significantly (P<0.05) higher than in those treated with Gd-DTPA (9.56×10(2)±6.15×10 p/s/cm(2)/sr) and Gd-DP (5.75×10(3)± 7.45×10(2) p/s/cm(2)/sr). Permeability of the nanoparticles modified by cell-penetrating peptides was superior to that of the unmodified counterpart, demonstrating the improved capability of nanoparticles for diffusion in tumor stroma on magnetic resonance imaging.

CONCLUSION

This study demonstrated that an image-guided gene delivery system with a stroma-permeable gene vector could be a potential clinically translatable gene therapy strategy for PDAC.

Radiofrequency ablation of unresectable colorectal liver metastases: trends in management and outcome during a decade at a single center

Background

Radiofrequency ablation (RFA) is widely used for treatment of colorectal liver metastases (CRLM).

Purpose

To evaluate the effect of increased experience in RFA of CRLM on morbidity and survival, and the trends in patient management and outcomes during the last decade.

Material and Methods

Hospital records of the initial 52 consecutive patients who underwent RFA (56 procedures/70 lesions) were retrospectively reviewed. The patients were divided into two groups according to time period of treatment, period I (2001–2006: n = 26) and period II (2007–2011: n = 26).

Results

Concomitant liver resection was performed in 15 patients in each period. Operative morbidity decreased from 47% to 19% (P = 0.047). Most complications were found in patients who underwent a concomitant liver resection and not related to the ablation per se. Local recurrence rate decreased from 19.4% to 12.9% (P = 0.526). At least one risk factor for recurrence was found in patients with local recurrence (n = 11): subcapsular localization (n = 4), tumor size >3 cm and subcapsular localization (n = 2), and perivascular localization (portal veins/hepatic veins) (n = 5). Median overall survival was 32 months in period I and 49 months in period II, whereas estimated 5-year survival was 19% and 36%, respectively (P = 0.09). Adjuvant chemotherapy was given to four patients (15.4%) in period I and 13 patients (50%) in period II (P = 0.017).

Conclusion

RFA alone or in combination with liver resection is a potentially curative treatment to selected patients with CRLM. Over time, the morbidity and survival have improved in RFA of CRLM. Although a possible effect of a learning curve should be taken into consideration in the appraisal of this improvement, it is more likely to be attributable to optimization of indication, development in surgical techniques, and increased use of perioperative chemotherapy.

Malignant ascites in patients with terminal cancer is effectively treated with permanent peritoneal catheter

Background

Malignant ascites is a pathological condition caused by intra- or extra-abdominal disseminated cancer. The object of treatment is palliation. In search of an effective and minimally invasive palliative treatment of malignant ascites placement of a permanent intra peritoneal catheter has been suggested.

Purpose

To evaluate our experiences with treatment of malignant ascites by implantation of a permanent PleurX catheter.

Material and Methods

A retrospective study was conducted, comprising 20 consecutive patients with terminal cancer, who had a permanent PleurX catheter implanted because of malignant ascites in the period from February to November 2014. Using the patients’ medical records, we retrieved data on patients and procedures.

Results

The technical success rate was 100%. Catheter patency was 95.2%, one catheter was removed due to dislocation. Ten patients (50.0%) experienced minor adverse events. No procedural difficulties were reported and there was no need for additional treatment of malignant ascites after catheter implantation. Median residual survival after catheter implantation was 27 days.

Conclusion

Implantation of a permanent PleurX catheter is a minimally invasive and effective procedure with only minor adverse events and a high rate of catheter patency in patients with malignant ascites caused by terminal cancer disease.

Nonvascular Interventional Procedures in an Urban General Hospital: Analysis of 2001-2010 with Comparison to the Previous Decade

RATIONALE AND OBJECTIVES

To determine trends in nonvascular image-guided procedures at an urban general hospital over a 10-year period and to compare utilization of nonvascular interventional radiology (IR) over the decade 2001-2010 to a previously reported analysis for 1991-2000.

METHODS

With institutional review board approval, a 20-year quality assurance database verified against the radiology information system was queried for procedure location (eg, pleura, liver, bowel, and abdomen) and type (eg, biopsy, catheter insertion, and transient drainage), demographics, and change over time. Yearly admissions and new hospital numbers assigned each year served to normalize for overall hospital activity.

RESULTS

A total of 50,195 IR procedures were performed in 24,309 distinct patients (male:female, 12,625:11,684; average age, 60 years), 940 procedures performed in age <20 years, and 571 procedures performed in patients aged ≥90 years. A total of 15345, 4377, and 1754 patients had one, two, or three procedures, respectively; 470 had ≥10 procedures. Twenty-seven supervising radiologists and 277 individuals participated as operators, double the previous decade. Biopsy (4.8% average yearly increase), abdominal drainage (7.3%), paracentesis (12.9%), tube manipulation (13.0%), suprapubic bladder tube insertion (21.0%), and gastrostomy (44.6%) all increased strongly (P < .001) over 120 months but not biliary drainage, nephrostomy, or chest tubes. Procedures increased faster than either admissions or new hospital numbers (P < .001). For each 1000 new hospital numbers, IR service performed 48 procedures versus 31 the previous decade (P < .0005).

CONCLUSIONS

Referrals for nonvascular IR procedures have doubled over 2 decades, outpacing growth in new hospital patients and requiring increased resource allocation.

Real-time distortion correction of spiral and echo planar images using the gradient system impulse response function

PURPOSE

MRI-guided interventions demand high frame rate imaging, making fast imaging techniques such as spiral imaging and echo planar imaging (EPI) appealing. In this study, we implemented a real-time distortion correction framework to enable the use of these fast acquisitions for interventional MRI.

METHODS

Distortions caused by gradient waveform inaccuracies were corrected using the gradient impulse response function (GIRF), which was measured by standard equipment and saved as a calibration file on the host computer. This file was used at runtime to calculate the predicted k-space trajectories for image reconstruction. Additionally, the off-resonance reconstruction frequency was modified in real time to interactively deblur spiral images.

RESULTS

Real-time distortion correction for arbitrary image orientations was achieved in phantoms and healthy human volunteers. The GIRF-predicted k-space trajectories matched measured k-space trajectories closely for spiral imaging. Spiral and EPI image distortion was visibly improved using the GIRF-predicted trajectories. The GIRF calibration file showed no systematic drift in 4 months and was demonstrated to correct distortions after 30 min of continuous scanning despite gradient heating. Interactive off-resonance reconstruction was used to sharpen anatomical boundaries during continuous imaging.

CONCLUSIONS

This real-time distortion correction framework will enable the use of these high frame rate imaging methods for MRI-guided interventions. Magn Reson Med 75:2278-2285, 2016. © 2015 Wiley Periodicals, Inc.

Ultrasonography in gastroenterology

Ultrasonography (US) is a safe and available real-time, high-resolution imaging method, which during the last decades has been increasingly integrated as a clinical tool in gastroenterology. New US applications have emerged with enforced data software and new technical solutions, including strain evaluation, three-dimensional imaging and use of ultrasound contrast agents. Specific gastroenterologic applications have been developed by combining US with other diagnostic or therapeutic methods, such as endoscopy, manometry, puncture needles, diathermy and stents. US provides detailed structural information about visceral organs without hazard to the patients and can play an important clinical role by reducing the need for invasive procedures. This paper presents different aspects of US in gastroenterology, with a special emphasis on the contribution from Nordic scientists in developing clinical applications.

Improved treatment of multidrug-resistant bacterial infections: utility of clinical studies

In a time of increasing antibacterial resistance and limited availability of new antibiotics, clinical studies are much needed to assess treatment options against multidrug-resistant organisms (MDROs). In this review, we describe the clinical challenge caused by MDROs and present recent evidence on how clinical studies may generate quality data to improve antibiotic treatment of MDRO infections. To this aim, we critically assess the current status, gaps and challenges associated with observational and interventional studies performed to assess MDRO treatment options. We address why observational studies are useful, which treatment options for MDRO have been explored by observational studies and how to improve quality and usefulness of observational studies. Furthermore, the utility of clinical pharmacokinetic/pharmacodynamic studies for improving MDRO treatment is described. Finally, we discuss interventional study designs, end points and margins, as well as ethical, logistic and statistical challenges, and current regulatory changes proposed to foster the development of new antibiotics.

Percutaneous biliary covered stent insertion in patients with malignant duodenobiliary obstruction

BACKGROUND

Although the use of polytetrafluoroethylene (PTFE)-covered biliary stents has proven to be feasible for the treatment of benign and malignant biliary disease, less is known regarding the outcomes of percutaneous placement of a covered stent in patients with malignant duodenobiliary obstruction.

PURPOSE

To investigate the technical and clinical efficacy of the percutaneous placement of a PTFE-covered biliary stent in patients with malignant duodenobiliary obstruction.

MATERIAL AND METHODS

From April 2007 to September 2012, the medical records of 45 consecutive patients with malignant duodenobiliary obstruction were retrospectively reviewed. All percutaneous biliary stent deployment was performed using PTFE-covered stents, whereas duodenal stent insertion was performed either fluoroscopically or endoscopically using covered or uncovered stents.

RESULTS

Biliary stent deployment was technically successful in all patients. None of the stents migrated after deployment. Procedure-related minor complications, including self-limiting hemobilia, occurred in three (7%) patients. Successful internal drainage was achieved in 39 (87%) of the 45 patients. The median survival time after biliary stent placement was 62 days (95% confidence interval, 8-116 days), and the cumulative stent patency rates at 1, 3, 6, and 12 months were 96%, 92%, 75%, and 38%, respectively. The causes of biliary stent dysfunction included stent occlusion caused by a subsequently inserted duodenal stent (n = 7), food impaction (n = 3), and sludge incrustation (n = 1). One patient developed acute cholecystitis 131 days after biliary stent placement and underwent percutaneous transhepatic gallbladder drainage.

CONCLUSION

Percutaneous insertion of a PTFE-covered stent is a safe and effective method for palliative treatment of patients with malignant duodenobiliary obstruction. If possible, subsequent biliary stent insertion is preferable in order to prevent possible biliary stent dysfunction caused by subsequent insertion of a duodenal stent.

Transarterial chemoembolization as first-line therapy for hepatocellular carcinomas infeasible for ultrasound-guided radiofrequency ablation: a retrospective cohort study of 116 patients

BACKGROUND

Ultrasound (US)-guided radiofrequency ablation (RFA) is frequently infeasible even for very early or early stage hepatocellular carcinoma (HCC) due to various reasons such as inconspicuous tumors or absence of a safe electrode path and the infeasibility rate is reportedly as high as 45%. In such cases, transarterial chemoembolization (TACE) is a commonly practiced alternative.

PURPOSE

To analyze long-term outcomes including tumor progression patterns and factors contributing to survival of patients who received TACE as the first line of therapy for very early or early stage HCC infeasible for US-guided RFA.

MATERIAL AND METHODS

From October 2006 through October 2009, 116 patients with very early or early stage HCCs underwent the first-line therapy TACE after their tumors were deemed infeasible for RFA. Long-term survival rates were calculated and prognostic factors were assessed by univariate and multivariate analyses. The patterns and rates of tumor progression or recurrence were also evaluated.

RESULTS

The 1, 3, and 5-year survival rates of the whole cohort were 94.7%, 68.4%, and 47.2% with a mean overall survival of 53.1 months (95% CI: 48.2-58.0). Preserved liver function with Child-Pugh class A was the only independent factor associated with longer survival. The most common first tumor progression pattern was intrahepatic distant recurrence. The cumulative rates of local tumor progression and intrahepatic distant recurrence at 1, 3, and 5 years were 33% and 22%, 52% and 49%, and 73% and 75%, respectively.

CONCLUSION

TACE is a viable first-line treatment of HCC infeasible for RFA, especially when liver function was preserved.

Intrapleural fluid infusion for MR-guided high-intensity focused ultrasound ablation in the liver dome

RATIONALE AND OBJECTIVES

Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation of tumors in the liver dome is challenging because of the presence of air in the costophrenic angle. In this study, we used a porcine liver model and a clinical MR-HIFU system to assess the feasibility and safety of using intrapleural fluid infusion (IPI) to create an acoustic window for MR-HIFU ablation in the liver dome.

MATERIALS AND METHODS

Healthy adult Dalland land pigs (n = 6) under general anesthesia were used with animal committee approval. Degassed saline (200-800 mL) was infused into the intrapleural space under ultrasound guidance. A clinical 1.5-T MR-HIFU system was used to perform sonications (4-mm treatment cells, 300-450 W, 20-30 seconds) in the liver dome under real-time MR thermometry. An intercostal firing technique was used to prevent rib heating in one experiment. Technical success was defined as a temperature increase (>10°C) in the target area. After termination, the animal was examined for thermal damage to liver, diaphragm, pleura, lung, or intercostal muscle.

RESULTS

An acoustic window was established in all animals. A temperature increase in the target area was achieved in all animals (max. 47°C-67°C). MR thermometry showed no heating outside the target area. Intercostal firing effectively reduced rib heating (55°C vs. 42°C). Postmortem examination revealed no unwanted thermal damage. One complication occurred, in the first experiment, because of an ill-suited needle (displacement of the needle).

CONCLUSIONS

The results indicate that IPI may be used safely to assist MR-HIFU ablation of tumors in the liver dome. For reliable tissue coagulation, IPI must be combined with an intercostal sonication technique. Considering the proportion of patients with tumors in the liver dome, IPI widens the applicability of MR-HIFU ablation for liver tumors considerably.

Transjejunal biliary interventions: going back to a road less traveled

Percutaneous transhepatic biliary interventions are not without risk and potential complications. In patients with bilioenteric anastomosis in whom repeat biliary interventions are expected, percutaneous transjejunal access is a very useful approach that is not frequently used nowadays. We provide a brief review of the history, indications, and current status of transjejunal biliary interventions. Transjejunal biliary access provides a relatively atraumatic pathway to the biliary system in patients that need repeat interventions. Multiple studies have provided convincing data that in appropriately chosen patients receiving a bilioenteric anastomosis, an antecolic limb of jejunum should be placed for subsequent access in biliary intervention.

Venous sac embolization of pulmonary arteriovenous malformation: safety and effectiveness at mid-term follow-up

BACKGROUND

The standard technique for the transcatheter treatment of pulmonary arteriovenous malformations (PAVMs) involves deploying coils into the feeding arteries. We investigated whether venous sac embolization would also be a safe and useful treatment method.

PURPOSE

To evaluate the safety and outcomes of venous sac embolization for PAVMs.

MATERIAL AND METHODS

This study included 15 consecutive patients (1 man, 14 women; mean age, 54 years; range, 22-76 years) with 50 PAVMs who underwent 26 procedures; four had a history of earlier cerebral infarction or exertional dyspnea. We first placed 0.018-inch interlocking detachable and/or 0.018-inch or 0.010-inch Guglielmi detachable coils to prevent systemic migration from the venous sac. We then packed the sac as tightly as possible and embolized the orifice at the proximal feeding artery. We used angiographic, clinical, and computed tomography (CT) studies to evaluate the treatment outcomes and safety of these procedures. The mean follow-up was 16 months (range, 3-63 months) in 12 patients with 43 PAVMs; three patients (7 PAVMs) were lost to follow-up.

RESULTS

Immediate post-embolization angiography confirmed complete primary occlusion in 47 of 50 lesions (94%). Minor complications arose in two of 26 procedures (7.7%); they were abnormal electrocardiograms without symptoms during and pleurisy immediately after the procedure. During follow-up, 40 PAVMs were free of CT evidence of reperfusion. The mean partial arterial oxygen pressure increased from 75.3% ± 13.6 before embolization to 85.4% ± 16.3 after embolization (P < 0.01, t-test). Of the 12 patients who were available for follow-up, none experienced new-onset paradoxical embolization; pre-treatment exertional dyspnea was alleviated in one patient. There were no major complications.

CONCLUSION

Venous sac embolization for PAVMs might be safe and more effective with no reperfusion than the standard pulmonary arterial embolization.

A study of clinical complications and risk factors in 1,001 native and transplant kidney biopsies in Sweden

BACKGROUND

In Sweden, native and transplant kidney biopsies are usually performed in major renal medical centers.

PURPOSE

To clarify risk factors in native and transplant kidney biopsies to improve patient safety.

MATERIAL AND METHODS

A total of 1001 biopsies (in 352 women and 565 men) were included. The median age was 54 years (range, 16-90 years). Data were derived from 826 native kidney biopsies (640 prospective and 186 retrospective) and 175 transplant kidney biopsies (170 prospective and 5 retrospective). Various factors and complications were registered while performing native and transplant kidney biopsies, focusing on major (e.g. blood transfusions, invasive procedures) and minor complications. The prospective protocol was used at six centers and at one center data were obtained retrospectively.

RESULTS

Women were at greater risk of overall complications than men (12.2% vs. 6.5%; P = 0.003; odds ratio [OR], 2.0; confidence interval [CI], 1.3-3.1) as well as of major complications (9.6% vs. 4.5%; P = 0.002; OR, 2.2, CI 1.3-3.7). Major complications occurred more commonly after biopsies from the right kidney, in women than in men (10.8% vs. 3.1%; P = 0.005; OR, 3.7; CI, 1.5-9.5), and in patients with lower BMI (25.5 vs. 27.3, P = 0.016) and of younger age (45 years vs. 52.5 years; P = 0.001). Lower mean arterial pressure in transplant kidney biopsies indicated a risk of major complications (90 mmHg vs. 98 mmHg; P = 0.039). Factors such as needle size, number of passes, serum creatinine, and eGFR did not influence complication rates.

CONCLUSION

The present findings motivate greater attention being paid to the risk of major side-effects after right-side biopsies from women's kidneys, as well as after biopsies from younger patients and patients with lower BMI.

Anesthesia for interventional radiology

Pediatric patients in the neurointerventional radiology setting pose the dual challenges of caring for relatively sick patients in the outfield environment. For safe and successful practice, the anesthesiologist must not only understand the nuances of pediatric anesthesia and the physiologic demands of the cerebral lesions. They must also help maintain a team-based approach to safe, compassionate care of the child in this challenging setting. In this review article, we summarize key aspects of success for several of these topics.

Retrospective study of the impact of fellowship training on two quality and safety measures in uterine artery embolization

RATIONALE AND OBJECTIVES

To measure the impact of 1-year interventional fellowship training on fluoroscopic time and contrast media utilization in uterine artery embolization (UAE).

MATERIALS AND METHODS

Retrospective single institution analysis of 323 consecutive UAEs performed by 12 interventional fellows using a standardized protocol. Fluoroscopy time and contrast media volume were recorded for each patient and correlated with stage of fellowship training. Preprocedure uterine volume (using MRI or ultrasound) was used as a measure of procedural complexity. Regression analysis was conducted per trainee factoring in duration of training, procedure number, supervising radiologist, uterine volume, and outcome variables of fluoroscopy time and contrast media volume.

RESULTS

Median number of patients treated per trainee was 27 (range, 16-43) with mean fluoroscopic time 24.5 minutes (range, 4-90 min) and mean contrast volume 190 mL (range, 50-320 mL). Increasing uterine volume had no significant effect (P > .05) on fluoroscopic time but significantly increased (P < .001) contrast media volume. Significant training effect was identified with decrease in fluoroscopic time (P < .001) and decrease in contrast volume (P = .02) over training. Over the course of a 1-year fellowship, these summed to a decrease of 12 minutes in UAE fluoroscopy time and 17 mL less contrast.

CONCLUSION

A significant (P < .05) training effect that is clinically relevant was demonstrated over the course of a yearlong interventional radiology fellowship program in performance of a standardized protocol for UAE. This data supports fellowship training as a basis for UAE credentialing and privileging.